title: Safety of Intravenous Thrombolysis within 4.5 h of symptom onset in patients with negative post-treatment stroke imaging for cerebral infarction.
abstract: BACKGROUND
  Patients with stroke symptoms but negative diffusion-weighted imaging (DWI) might have transient ischemic attacks (TIA) or stroke mimics. Brain DWI is important for the diagnosis of cerebral infarction but it is not available before thrombolysis for most patients to avoid treatment delay. This study aimed to evaluate the safety of IV thrombolysis in patients with a negative post-treatment DWI for cerebral infarction.
  
  
  METHODS
  We conducted a retrospective study of 89 patients treated with IV recombinant tissue plasminogen activator (rt-PA) within 4.5 h after stroke symptom onset. The patients were identified in our acute stroke registry from January 2009 to September 2010. Information on patients' demographics, clinical characteristics, neuroimaging, treatment complications, and outcomes was obtained and analyzed.
  
  
  RESULTS
  Out of 89 patients, 23 patients (26%) had a negative DWI on follow-up stroke imaging. Fourteen patients had a TIA and nine patients had a stroke mimic, including Todd's paralysis, complicated migraine, and somatoform disorder. We found significant differences between patients with a positive and a negative DWI in mean age (62 years vs. 52 years; P < 0.01) and median admission NIH stroke scale score (11 points versus 6 points; P < 0.001). Among patients with a positive DWI, four patients had a symptomatic intracerebral hemorrhage (ICH). No patients with a negative DWI had symptomatic or asymptomatic ICH.
  
  
  CONCLUSIONS
  Our results suggest that the administration of IV rt-PA within the first 4.5 h of symptom onset in patients with suspected ischemic stroke is safe even when post-treatment DWI does not demonstrate cerebral infarction.
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. giraldo.elias@mayo.edu
authors.forename: Elias A
authors.initials: EA
authors.lastname: Giraldo
authors.forename: Aisha
authors.initials: A
authors.lastname: Khalid
authors.forename: Ramin
authors.initials: R
authors.lastname: Zand
mesh_terms: D000368:Aged; D002544:Cerebral Infarction / Q000175:diagnosis / Q000628:therapy*; D038524:Diffusion Magnetic Resonance Imaging; D004334:Drug Administration Schedule; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage*; D006801:Humans; D002546:Ischemic Attack, Transient / Q000175:diagnosis / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D020521:Stroke / Q000175:diagnosis / Q000209:etiology / Q000628:therapy*; D015912:Thrombolytic Therapy; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage*; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator